The numbers a , b , and c are positive and a equals 3.2bc . If b is increased by 150% and c is decreased by 60%, then a is

Correct answer: C. unchanged

  • A. increased by 90%
  • B. increased by 10%
  • C. unchanged
  • D. decreased by 10%

Explanation

The given equation is a = 3.2bc. We are told that b is increased by 150%, making the new value of b = 2.5b (since 150% of b is 1.5b, adding this to the original b gives 2.5b). Similarly, c is decreased by 60%, making the new value of c = 0.4c (since 60% of c is 0.6c, subtracting this from the original c gives 0.4c).Substituting these new values into the equation for a gives: New a = 3.2 * 2.5b * 0.4c = 3.2bc. This is exactly the same as the original value of a, showing that a is unchanged despite changes in b and c.Therefore, the correct answer is Option C: unchanged. The other options are incorrect as they suggest changes in the value of a that do not occur based on the given percentage adjustments.

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